1. Field of the Invention
The present invention relates to a resonant frequency adjustor and more specifically a resonant frequency adjustor for controlling noise and vibration from an exhaust system of a vehicle and method of utilizing the same.
2. Description of the Prior Art
Combustion engines of vehicles are required to operate over a wide range of speeds (i.e. idle to wide open throttle), and flow the resultant exhaust gas through an exhaust system to in-part muffle noise, route potentially toxic fumes to a safe location toward the rear of the vehicle, and at least partially reduce emissions hazardous to the environment. With varying engine speeds, varying engine vibration is transmitted to the exhaust pipe of the exhaust system along with the varying flow of exhaust gas. The transmitted engine vibration and the exhaust gas flow contribute toward vibration of the exhaust system and pipe. This vibration of the exhaust system can be transferred to the rest of the vehicle and may also affect the sound emitted by the exhaust system.
For luxury vehicles that typically strive to reduce noise and vibration within the passenger compartment to a minimum, any vibration and noise transmitted from the exhaust system is generally undesirable. For some sport vehicle applications, transmitted vibration from the exhaust system is generally undesirable, however, certain noises such as a deem rumbling sound may be desirable from the exhaust system. Regardless, undesirable vibration of the exhaust system that is typically transmitted through a frame or chassis of the vehicle and into of the interior is typically annoying and adds to discomfort for a vehicle passenger.
Mounts used to mount the exhaust pipe to the frame of the automobile may be used to isolate the vibration of the exhaust pipe preventing its transmission to the frame. Such mounts are generally expensive and some materials of the mounts may degrade over time thereby allowing increased vibration transfer to the frame. For exhaust systems having resonating frequency(s) that generally conform or match the vibrations produced by the engine and exhaust flow at a common engine speed, that degradation rate of such mounts can be further aggravated.
Additionally, some vibrations of certain frequencies may have a desirable affect on the sound emitted by the exhaust system. For example, a persona of a vehicle may be defined by a roaring or rumbling exhaust sound. More specifically, such a roar or rumble may be desirable if the vehicle is a motorcycle or an automobile such as a so called hot rod or muscle car.
It is desirable to manufacture a resonant frequency adjustor that may dampen the vibration of an exhaust pipe of a vehicle to minimize the vibration transferred to the adjacent frame. In addition, it is desirable to manufacture a resonant frequency adjustor that may also be used to tune the sound emitted by the exhaust system.